﻿/*
数字字串 
Time Limit:1000MS  Memory Limit:32768K

  
	Description:
	输入一些字串，判断其是否为数字字串。
	
Sample Input:
120D3
012
Sample Output:
No
Yes

*/
#include <stdio.h>
#include <string.h>
#include <ctype.h>
#define MAX_CHARS 512
int main(int argc, char* argv[])
{
	char line[MAX_CHARS];
	while (gets(line))
	{
		char* p;
		for (p=line; *p; ++p)
			if(!isdigit(*p))
				break;
		if(0==strlen(line)||*p)
			printf("No\n");
		else
			printf("Yes\n");
	}
	
	return 0;
}